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303C Where to test and what pressure?

Mcgyvr · 2020-07-31 09:30

Ok, we dont have much for power to the tracks i have confirmed the rabbit turtle mode is working (thanks to here) both tracks seem to be of equal power, as it warms up it is noticeably weaker it will push OK with both but will not turn just one in either direction and in dirt it will only try to turn on its weight with sticks in opposite directions, this has been slowly getting worse in the last couple of years. Pressure check where and how much and adjustment location? Hydraulic Fluid & filt. changed every 1000 0W40 used as it can get cold in Atlantic Canada. Thanks

Replies6
  1. #1Nige2020-08-01 04:01

    Have you tried resealing the centre swivel..? For the symptoms you describe and a machine of that age the seals are most likely hardened with age and allowing oil to leak from one circuit to another.

  2. #2Mbar2020-08-03 17:37

    I’m with nige. Another simple thing to check is are you actually getting full stroke out of your travel levers. Could be dirt or debris. Or just worn parts.

  3. #3Mcgyvr2020-10-15 09:56

    so yes the swivel had been done also both track motor reliefs by a CAT Tech., everything pointed to the pump FLOW but after a rebuild of THOUSANDS it still has the issue. Does anyone have a hydraulic schematic? We have someone different trying to figure it out.

  4. #4Nige2020-10-15 10:05

    Serial Number please, in order to locate correct schematic.

  5. #5TVA2020-10-15 17:19

    Those pumps don’t have flow adjustments, the variable displacement on those just for the pressure compensation ( at set pressure pump will de stroke to regulate the pressure) If the pressure below set value - piston pump(s, because there’s two pumps in the same housing) basically fixed displacement! If only problems you have is travel, and you 100% sure your center swivel is good - then what left is pilot pressure - strainer in the inlet fitting to the pilot valve ( pedal) might be plugged. Or the problem in the motor. I just finished messing with arm spool in 304, so spool can get stuck too! Because in their infinite wisdom Mitsubishi/MCT installed main control valve underneath of the cabs floor - I really do not envy you trying to read pilot pressure at the actuators!!!

  6. #6Mcgyvr2020-10-20 09:18

    *CAT0303CCBXT05016*